The invention relates to a framed glazing unit, and in particular to such a unit which is openable such as a door, especially a door that is commonly referred to as an all-glass door, or a window, or to such a unit which is fixed and mounted in a glazing assembly adjacent to or in the vicinity of a door or a window and may incorporate hinge, lock, closer, stay or stop fittings, such as a transom panel (otherwise referred to as a fanlight), a door side panel (otherwise referred to as a door side section or a door side light), or similar.
Such an all-glass door of known construction normally consists, apart from its fittings, solely of a glass sheet. Known doors of this type have compact glass sheets. In many cases, the thermal conductivity of such doors is unacceptably high. The same applies to door side sections, fanlights, windows or similar.